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6-4-5. Alarm setpoint setting
This section describes the settings for the first to third alarm setpoints, STEL alarm setpoint, and TWA
alarm setpoint and how to restore the default settings.
<Alarm setpoint setting>
Alarm setpoints can be set using one-digit units.
Detection target gas 1 digit Lower limit Upper limit
Combustible gas (HC/CH
4
) 1 %LEL 5 %LEL 60 %LEL
Carbon monoxide (CO) 1 ppm 20 ppm 2,000 ppm
Hydrogen sulfide (H
2
S
)
0.1 ppm 1.0 ppm 200.0 ppm
Detection target gas 1 digit
First/second alarm Third alarm
Lower limit Upper limit Lower limit Upper limit
Oxygen (O
2
) 0.1 vol% 0.0 % 20.0 % 21.8 % 40.0 %
NOTE
Set the alarm setpoints as follows: First alarm ≤ second alarm ≤ third alarm (first alarm ≥ second
alarm for oxygen)
1
Press the AIR button on the user mode
menu to select “ALARM-PT”, then
press the MODE button.
2
Press the AIR button to select the gas
type, then press the MODE button.
Pressing the AIR button alternately displays the
detection target gas and the alarm setpoint reset
screen (page 53).
Pressing the MODE button displays the first alarm
setpoint (WARNING) setting screen.
3
Press the AIR button to select a
numerical value for the first alarm
setpoint, then press the MODE button.
The second alarm setpoint (ALARM) setting screen is
displayed.
4
Press the AIR button to select the
second alarm setpoint numerical
value, then press the MODE button.
The third alarm setpoint (ALARM H) setting screen is
displayed.
5
Press the AIR button to select the
third alarm setpoint numerical value,
then press the MODE button.
For toxic gas, the STEL and TWA setting screens are
displayed after the above steps. Set these in the
same way.
“END” appears and the alarm setpoint reset screen
appears.